[solved] Huge Kemper Latency

  • Hi there, I have been reading everything I have found about Kemper and its latency.

    In the manual says that even setting the Constant Latency parameter to ON, the maximum latency should be something around 4.9ms- But actually, recording via spdif, the minimum latency I have got have been 343 samples, and that means 7.7ms, and it is with NO Stomps, No Rig, No effects, NO Nothing. But If I use some preset, even in the case it has just the rig on, I can have no less than 1252 samples, and that means 28,39ms.


    I'm talking from a profesional studio with a very powerful Mac with 64 gigas of Ram, a ProTools HDX with two cards in its last version 2019.5, although just in case, I tried with two previous versions as well.


    Many people says that no one can detect 343 samples of latency, but I have had recording today a profesional session guitarist in my studio that has got literally mad recording with the kemper. Fortunately I have recorded the clean signal as well, so I think I will be able to put them in sync taking in count the clean version.


    My configuration is:


    1) I'm recording with a sample rate of 44.1Khz and a buffer size of 128 samples.

    2) Guitar goes to a Lehle Split II to split the signal in two signals. (Lehle does not ad latency at all)

    3) One Lehle's output goes straight to ProTools and I record that clean guitar in a track.

    4) Another Lehle's output goes to a real amp and its cabinet, then I record that signal in a separate track in ProTools.

    5) I use the Kemper as an insert in track that has the direct input signal of the guitar, and I send that signal to another track (with a send) or sending the clean signal throughout a bus.


    As a result I have got a clean version of the guitar perfectly in sync with the signal coming from the real amp / cabinet, and a minimum 343 samples delayed guitar coming from the Kemper. I say minimum, because normally I can have no less than 1252 samples of latency with just a rig and a compressor in the stomps.


    Is it normal that amount of latency?

    Is my Kemper unit bad?

    It's pretty new, I bought it in Thomann around a month, maybe more, but I could not record with it until today.


    Please, Any advise about how to solve my problem?


    Thanks in advance!

  • You don’t say how the Kemper is connected; via analogue xlr or spdif? Personally, I’d skip the Lehle and go into the kpa, record either the direct out and the analogue xlr, or spdif set to record master mono and git analog. Then you can route the dry direct signal from there in PT to the amp and/or any plugins you wish. There shouldn’t be any discernible latency while playing, so something in your routing is causing it.

    Always try the simplest, most direct set up first when troubleshooting, to determine the cause. In my scenario above, I’d turn off the constant latency. I can understand why you’d use it in your scenario, but it’s really only intended for use when reamping, to maintain phase relationships when layering different rigs.


    Edit : remember to set the kpa to master in PT when using spdif!

  • I'm certain digbob nailed it.


    Monitoring the Kemper "at-source" via the interface or an auxiliary mixer is the only real solution and one that I and many others subscribe to.

  • Hi there,

    sorry for the missing information. I am using SPDIF as input / output, but I have checked other options, including recording guitar going directly the Kemper input and going out to PT thru the Kemper direct output, but all of those ins / outs create more latency than the SPDIF protocol.


    In addition, I'm not using CONSTANT LATENCY, because I have understood that it would introduce even more latency in the chain.


    BTW, Lehle Split II does not enter any latency at all, ZERO latency. I have used many, many times in my set to record two amps at the same time with no latency at all. Everything is completely in sync if I do not use the kemper.


    Finally, whatever digital hardware inserted in my configuration adds only around 8-11 samples of latency. I have several digital outboard gears connected in my system like a TC-6000, My own digital ADA converter, which I use all the time in my work, some digital pre-amps, and I can say that I have zero latency with them.


    The only problem here is the Kemper. No matter I record digital, analog, whatever I have a huge latency. Many times, you can even note clearly that the first note that comes from guitar is even more delayed than the next one. It's funny! It's not constant! It works like a machine which starting the engine. So professionally talking, you can not play with them without going crazy with the delay between the different signals.


    I have done as much tests as I could before posting anything here, because my only concern is if my unit is malfunctioning or is working as expected.


    Could someone let me know if this behaviour is normal?

    Any idea about how to fix it?


    Thanks in advance!

  • BTW, I have the Kemper operative system as well as the rig manager completely updated.

    And remember this is a professional studio, and even any cable here is a Mogamy, VoVox or Monster Cable.

    It make no sense all this amount of latency with a new hardware.


    Thanks in advance!

  • What do you mean with "Set the Kpa to master"? Is there any hidden parameter in the Kemper that I must set while using Spdif?

    Let me know!

    Not in the KPA but in your sound interface's control software. I guess it's already set to master, because otherwise you'd likely have clicks and pops in your sound.


    I don't find any perceivable latency in my unit when I play. Only a bit when using some transposing / pitch-shifting effects.

  • From the manual :


    • Your audio interface must be set as a clock slave to S/PDIF, since the PROFILER itself is not able to act as slave of an incoming S/PDIF clock.

    • The PROFILER can generate a clock of 44.1, 48, 88.2, or 96 kHz. Your audio interface and DAW will be clocked at the selected rate and your DAW project should also be set accordingly.

    • For the DI recording, only one cable is required from the S/PDIF OUTPUT of the PROFILER to the input of your audio interface. • For reamping, you will need to connect a cable from the S/PDIF OUTPUT of the audio interface to the S/PDIF INPUT of the PROFILER. The connection from the S/PDIF OUTPUT of the PROFILER is still required to feed the S/PDIF clock to your audio interface.

  • No, latency of the nature you describe would make the KPA unsellable. There is either something wrong with your setup, or you have a faulty profiler.


    Again, to troubleshoot, I’d start as simply as possible. Guitar->Kemper->headphones. If there’s detectable latency here, you have a faulty unit.


    Edit : just a thought, but check your output menu isn’t set to only output the wet signal, meaning you are only hearing the 100% mix of any delay or reverb you have active.


  • Could someone let me know if this behaviour is normal?

    Any idea about how to fix it?


    Thanks in advance!


    This is not normal behaviour. I play happily all the time either direct monitoring from my desk or through SPDIF from DAW track.


    BTW, Lehle Split II does not enter any latency at all, ZERO latency. I have used many, many times in my set to record two amps at the same time with no latency at all. Everything is completely in sync if I do not use the kemper.

    you shouldn’t even need the Lehle as its possible to send the Analog DI signal straight to you interface without going through the KPA’s converters by setting Git Analog as the source for the Direct Out.

  • Guitar->Kemper->headphones.

    Beat me to it, SamBro'. ;)


    Hermes, it's stating the obvious, but doing the above is equivalent, latency-wise, to doing what I suggested earlier:

    Monitoring the Kemper "at-source" via the interface or an auxiliary mixer is the only real solution and one that I and many others subscribe to.

    I'm guessing you'll experience 2.5->3.5ms latency, the equivalent of placing your ears a few feet from a "real" amp.


    Add a couple o' ms to this if you use an interface's internal routing to feed an analogue monitor mix due to the additional A/D and D/A conversions necessary. Either way, it shouldn't be much more than 5ms overall even with those extra conversions.


    I'm also guessing that you'd be aware of this stuff, so, short of the unlikely possibility that the issue is your Kemper, please revisit your monitoring approach in your DAW. You didn't mention anything about this or checking your settings when you responded here.

  • Something else, SPDIF doesn’t automatically mean less latency, not all audio cards or drivers are made equal. Try using the Kemper via analog.


    A passive splitter like the lehle split shouldn’t introduce any perceivable latency, it’s like having a y cable in there and a switch for polarity. I.e. it’s the same as a guitar cable despite its nice housing. I wouldn’t use it as a guide for anything. Digital FX like the Kemper must do their own conversion which will introduce latency.


    Check also how you’re sending audio to the Kemper. If it’s also via spdif the the problem is most likely your audio interface and it’s latency. Your PT rig is probably set up with latency compensation enabled which will help align tracks as they come in, however when you introduce a spdif round trip it can mess things up, only the return may be compensated for.


    Finally if all else fails and you’ve tried these suggestions and everyone else’ suggestions try a factory reset on the Kemper itself and failing that getting in touch with the support team. Your Kemper should add no more latency than any other digital guitar fx unit or stomp.

  • Just try the profiler with headphones and a guitar. If there's no latency then there's something bottlenecking your set up. If there is then either you are too sensitive to lag or there's something wrong with the profiler. If you try this then at least you will have moved one step closer to solving your issue...

  • Hi everybody, and first of all, thank you so much for all your help on this. I am so happy that kemper's community is so friendly and willing to help.

    I have made more testings, following your advices, and I'm still having a latency around 889 samples (20ms) recording at 44.1khz with no rig, nothing in the stomps or effects, and something around 1170 with a basic preset with a rig, a chorus in the stomps and a delay and rever in the effects.


    This is what I have done: (BTW, I made my testings with an old drum machine which has a clear sidestick to see the sound wave generated.)


    1) Drum machine connected to my lehle split II

    2) One Lehle's output to the analog front input of the KPA

    3) The other Lehle's output directly to an API Preamp which output I have recorded in track 4.

    4) Already inside the kemper, I am using the analog main outputs, and the direct output with then Git analog signal


    So, I have been recording at the same time the following tracks

    Track 1 - Analog Main Output Left from KPA

    Track 2 - Analog Main Output Right from KPA

    Track 3 - Direct Output from KPA

    Track 4 - Direct signal from my drum machine coming from one of the two Lehle's outputs. In this track I have set a buss (pre-fader mode) with the SPDIF signal of the Kemper.

    Track 5 - (Stereo track) - I take the signal of the bus inserted in track 4 and I recorded that.


    The result has been that...


    Tracks 3 & 4 are completely in sync as expected. I mean the direct output coming from KPA, and the direct signal coming from my Lehle are completely in sync. Well... I can see maybe a half of sample of difference in the waveform. :-)


    Between Tracks 1 & 2 (Main KPA outputs) and Track 5 (SPDIF output) there is a difference of 169 samples 3,8ms at 44,1khz.


    Between Tracks 1 & 2 and Track 3 or 4 there is a latency of 889 samples (20 ms) at 44.1khz using No rig, nor nothing in the stomps of effects, and 1170 samples (26ms) at 44.1khz using the amp and a cabinet, as well as a chorus in the stomp and a delay an rever in the effect section.


    Maybe I'm so sensitive to lag, hehe But honestly, playing some eighth notes with guitar mute in a funky song becomes very hard with this amount of latency. I'm sure you understand me.

    Finally if all else fails and you’ve tried these suggestions and everyone else’ suggestions try a factory reset on the Kemper itself and failing that getting in touch with the support team. Your Kemper should add no more latency than any other digital guitar fx unit or stomp.

    I will try to reset the unit and check if something changes as Per suggested here, and I will let you know if that made the trick. But I am not sure this is the problem here.


    I will keep you posted!


    Thanks again for your help on this.

  • After a Global reset (pressing the system button while turning the power button to browser position) unfortunately nothing has changed!

    I am still getting the same latency.


    I will try to contact with the Kemper's support team.

    Fingers crossed!

  • Have you tried the most-basic test of all - to plug a guitar in and play whilst monitoring from the Kemper's headphone output, Hermes?


    A few of us have suggested this but you've not mentioned it in your test reports.

  • One other thing, what rigs are you using (with what stomps)? Certain stomp effects will add quite noticeable delay, e.g. anything pitch shifting for instance instantly adds several hundred samples. Do you also have the "space" setting disabled (check other output settings) and what about the noise gate (my personal pet peeve, I always have this locked to off in the input section)?


    What happens if you literally turn off the entire rig and just have clean signal through? If there's a large latency gap still between the DI and Kemper signal when both are going through analog inputs on your sound card (no more SPDIF) then that's definitely something that needs looking in-to.


    One thing I would like in a future version of a Kemper is lower latency in general, sound cards these days are able to deliver extremely low latency levels without taxing the computer CPU (lower than the Kemper achieves), even though 5ms is not "noticeable" it kinda is somehow when next to the real analog deal and 8ms definitely is albeit subtly and definitely feels like more work.